Ape Genius (Feb. 2008)

Experts zero in on what separates humans from our closest living relatives. Watch now (49 mins.)

Cracking the Code of Life (Apr. 2001)

Follow the race to decode the human genome and see how this newfound knowledge is already changing medicine. Watch now (105 mins.)

The Incredible Journey of the Butterflies (Jan. 2009)

Follow the 2,000-mile migration of monarchs to a sanctuary in the highlands of Mexico. Watch now (50 mins.)

Ocean Animal Emergency (Nov. 2008)

Wildlife veterinarians struggle to save injured seals and sea lions on the California coast. Watch now (50 mins.)

The Four-Winged Dinosaur (Feb. 2008)

Surprising fossils from northeastern China spur a debate over how birds evolved. Watch now (50 mins.)

Judgment Day: Intelligent Design on Trial (Nov. 2007)

Science is 'Exhibit A' in a landmark trial on the teaching of evolution. Watch now (108 mins.)

Lizard Kings (Oct. 2009)

Meet the monitors, the largest, fiercest and craftiest lizards on Earth. Watch now (50 mins.)

Lord of the Ants (May 2008)

Naturalist E.O. Wilson's fascination with little creatures has led him to some very big ideas. Watch now (50 mins.)

Profile: Maydianne Andrade (July 2009)

By peering into the sex lives of Australian redback spiders, this evolutionary biologist has shown the upside of cannibalism. Watch now (15 mins.)

Profile: Sangeeta Bhatia (July 2009)

Intrigued by the idea of artificial organs, a biomedical engineer uses computer-chip technology to craft tiny livers. Watch now (15 mins.)

Rat Attack (Feb. 2009)

Why do huge swarms of rats overrun a bamboo forest in India once every half-century? Watch now (50 mins.)

Smart Sea Lions and Talking Walruses (July 2009)

Marine mammals are wowing researchers with more than just circus tricks Watch now (15 mins.)